Assessment of hepatitis B virus DNA levels in chronic HBsAg carriers with or without hepatitis delta virus superinfection

Spontaneous exacerbation of disease activity in patients with chronic delta hepatitis infection: the role of hepatitis B, C or D?

Forty-six patients with chronic hepatitis delta virus infection were followed between 6 and 116 mo (mean = 32.8 mo; median = 24 mo). Nineteen patients (41%) demonstrated clinical courses with episodes of biochemical reactivation (ALT levels greater than or equal to 10 times baseline values [group A]). Twenty-seven patients (59%) had stable clinical courses without biochemical reactivation (group B). Patients in group A were younger than those in group B (30.5 vs. 35.3 yr; p = 0.03), were less likely to be intravenous drug abusers (16% vs. 52%; p = 0.01) and were more likely to be homosexual (58% vs. 22%; p = 0.01). Serum hepatitis B virus DNA, hepatitis delta virus RNA, IgM antibody to HBc, HBeAg, antibody to HBe and IgG and IgM antibody to hepatitis delta virus were measured in all patients. In group A, these markers were studied before and during reactivation and during remission. In group B, these parameters were studied in a random fashion at 7- to 10-mo intervals. The presence of antibodies to human immunodeficiency virus and hepatitis C virus was assessed in all patients. A total of 38 biochemical reactivation episodes was noted among the 19 patients in group A. Eleven had sequential changes in hepatitis delta virus markers, suggesting that the exacerbations were due to hepatitis delta virus. In three, the sequential changes of viral markers were consistent with the exacerbations due to hepatitis B virus. In five other patients, no sequential changes in viral markers could be demonstrated to correlate with the biochemical exacerbations.(ABSTRACT TRUNCATED AT 250 WORDS)

Intrahepatic expression of hepatitis B core and surface antigens in chronic hepatitis delta-virus infection

To evaluate the interference of hepatitis B virus (HBV) protein expression in the liver in chronic hepatitis delta-virus (HDV) infection, the intrahepatic expression of hepatitis B core and surface antigens (HBcAg and HBsAg) was studied in 36 HBsAg carriers who were seropositive for anti-HDV and in 36 anti-HDV negative controls [18 with serum hepatitis B e-antigen (HBeAg) and 18 with anti-HBe]. Of 18 HBeAg-positive patients with anti-HDV, 12 had HDV antigen (HDAg) in the liver. HBcAg was positive in 66.7% (8/12) of the HbeAg-positive patients with HDAg in the liver, and in 94.4% (17/18) of controls (p = 0.14). The distribution of HBcAg was exclusively cytoplasmic in 75% (6/8) of HDV-infected patients, but was mixed nuclear and cytoplasmic in 70.6% (12/17) of the controls. The prevalence and quantitative expression of HBcAg in the nucleus, but not in the cytoplasm, were significantly decreased in chronic HDV infection. HBsAg was positive in 91.6% (11/12) of HBeAg-positive patients with HDV infection and in all controls. Membranous expression of HBsAg was detected less frequently in HDV-infected patients than in controls (7/12 vs. 17/18, p = 0.05), while the prevalence and quantitative expression of HBsAg in the cytoplasm showed little or no difference. HDAg was detected in all of the anti-HBe-positive patients with anti-HDV. Of these, none had HBcAg detectable in the liver, nor did controls, while HBsAg was detected exclusively in the cytoplasm in 94.4% (17/18). The prevalence and quantitative expression of HBsAg in the cytoplasm was not different for HDV-infected patients or controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Co-expression of markers for hepatitis delta and hepatitis B viruses in human liver

Delta hepatitis (HDV) infection can only occur in the presence of hepatitis B (HBV) infection, as HDV requires a coat of HBV surface antigen (HBsAg) for assembly of complete virus. A number of studies have examined the variation of HBV markers in serum and liver during establishment of HDV infection, but none has systematically examined the relationship between the two viruses in individual hepatocytes. Liver biopsies from five patients with HDV/HBV infection were stained for HBsAg, HBV core antigen (HBcAg) and hepatitis D (delta) antigen (HDAg). Double immunostaining was performed with a combination of indirect immunoperoxidase and alkaline phosphatase/antialkaline phosphatase techniques. HDV and HBV antigens were expressed in all five liver biopsies. Co-localization of HBsAg was seen in up to 39% of HDAg positive cells, and HBcAg in up to 8% of HDAg positive cells. HBcAg was detectable in approximately 9% of HBsAg positive cells, and HBsAg in approximately 12% of HBcAg positive cells. HDV can replicate without HBV but ultimately requires HBV to produce complete virus and subsequently infect other cells. In this study the majority of HDV positive cells did not appear to contain HBV markers. This might suggest delta virus replication without assembly, or possibly sequential production/assembly of the virus.

Influence of hepatitis delta virus replication in the presence of hepatitis B virus DNA in peripheral blood mononuclear cells

The presence of hepatitis B virus DNA was studied in peripheral blood mononuclear cell samples from 259 HBsAg carriers (229 anti-hepatitis delta negative, 30 anti-hepatitis delta positive), 16 anti-HBc-positive HBsAg-negative patients and 30 patients without hepatitis B virus markers. Hepatitis B virus DNA sequences were detected in peripheral blood mononuclear cell from 115 (44.4%) of the chronic HBsAg carriers and from two (12%) of the anti-HBc-positive, HBsAg-negative patients. In anti-hepatitis delta-negative patients, viral DNA was positive in peripheral blood mononuclear cell from 74 (46%) and from 24 (35.5%) with and without serum HBV-DNA, respectively. With respect to anti-hepatitis delta-positive patients, viral DNA was found in peripheral blood mononuclear cell in 8 of 13 (61.5%) of the patients with circulating hepatitis delta virus RNA and in 9 of 17 (53%) of the hepatitis delta virus RNA-negative subjects. Regarding hepatitis B virus DNA in serum and peripheral blood mononuclear cell, 71% (5 of 7) of the patients with serum hepatitis B virus DNA had this marker in peripheral blood mononuclear cell, whereas 52% (12 of 23) of the patients without serum hepatitis B virus DNA had hepatitis B virus DNA in peripheral blood mononuclear cell. A Southern blot analysis was also carried out on peripheral blood mononuclear cell samples from 30 patients. Hepatitis B virus DNA was detected in 16 patients as free forms, in 12 patients as dimers and free forms and as free circular together with free linear forms in the remaining two patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Immuno-light and electron microscopic features of chronic hepatitis D

A morphologic study with immunohistochemical detection of the viral antigens of hepatitis B and Delta was performed on 36 liver specimens from patients with delta positive chronic viral hepatitis B. Electron microscopy was performed in 9 cases. No light microscopic or ultrastructural features specific for hepatitis D were observed. Lymphocytic infiltration occurred more often close to hepatocytes containing either hepatitis Delta antigen or hepatitis B core antigen in the cytoplasm, suggesting an involvement of cellular immune mechanisms in chronic hepatitis D as well as in hepatitis B. The simultaneous expression of both HBcAg and Delta antigen in occasional specimens over longer time periods indicates the possible co-existence of both viruses without mutual inhibition.